Apple Watch Ultra Crown not moving or very stiff

So I have AW Ultra for 1 week and I swim every day with it, first 2-3 days everything was fine but on the 4th day something happened and it happened not just after the swim but on the 5th day in the morning. When I got up and tried to turn the crown, it was stuck and it needed hard effort from my finger to unstuck it, then I continued rotating it and the crown was rotating only by 1mm and then becoming very resistant again like it was very dirty inside.

I use the water ejecting maybe 10 times after the pool, I wash it in clear water and everything how apple is instructing but every day the crown becomes more stiffer in the morning when it's not been moved for hours and I have been swimming the previous day.